Tunnel-boring rotary head with adjustably mounted gauge cutters



1966 R. J. ROBBINS ETAL 3,232,670

TUNNEL-BORING ROTARY HEAD WITH ADJUSTABLY MOUNTED GAUGE CUTTERS 2Sheets-Shee t iled Aug. '7, 1964 DOUGLAS F. WINBERG INVENTOR.

- RICHARD J. ROBBINS ATTORNEYS Feb 1956 R. J. ROBBINS ETAL 3,232,670

TUNNEL-BORING ROTARY HEAD WITH ADJUSTABLY MOUNTED GAUGE CUTTERS FiledAug. 7, 1964 2 Sheets-Sheet 2 Q! Egg; a; v- V RICHARD J. ROBBINS DOUGLASF. WINBERG INVENTOR.

ATTORNEYS United States Patent Office 3,232,670 Patented Feb. 1, 19663,232,670 TUNNEL-BORING ROTARY HEAD WITH ADJUST- ABLY MOUNTED GAUGECUTTERS Richard J. Robbins, Seattle, and Douglas F. Wiuberg,

Bellevue, Wash, assignors to James S. Robbins &

Associates, Inc., Seattle, Wash., a corporation of Washington Filed Aug.7, 1964, Ser. No. 388,089 15 Claims. (Cl. 29956) The present applicationis a continuation-in-part of copending application Serial No. 259,275,filed February 18, 1963, now abandoned.

This invention relates generally to that type of machine which borestunnels of a relatively large diameter in a manner such that the machineitself travels progressively into the ground strata being bored as itslarge rotary head cuts a passage in the rock, and relates moreparticularly to the manner of mounting special cutters which are carriedby the head at the perimeter thereof to perform a cutting operation uponrock proximal to the side Wall of the tunnel which is being bored.

Several co-pending patent applications also relate to the above-namedboring machine. One of these, entitled, Head Structure for Rock DrillingMachine, Serial No. 203,846, filed June 20, 1962, pertains to much thesame type of rotary head which carries the present cutter mountings. Itis believed clarity in an understanding of the features to which thepresent application is particuarly directed will be advanced by herecursorily describing the general nature of the boring machine andsomewhat more specifically the structure and operation of the machinesrotary head.

The machine provides a relatively large body portion having a diametermoderately less than the tunnel which is to be bored, and desirably hasa length greater than its diameter. There are mounted on the body ofthis machine a plurality of shoes arranged to be pressed outwardly so asto grip the side wall of the tunnel. By retracting one pair ofdiametrically opposed shoes from the tunnel wall, moving this pair ofshoes forward, and then again pressing the latter shoes outwardly totake a new grip on the turmel wall, the machine is able to walk alongthe length of the tunnel.

Mounted at the front of the body for rotary motion about thelongitudinal axis of the machine is a large circular head, having afront plate which faces the end wall of the tunnel from which the rockis being cut. This head is powered for rotary motion and also forprogressive axial motion in the intervals between the steps of saidwalking travel. The head carries a plurality of outrigger bucket memberswhich are or may be evenly spaced along the circumference of the head.Cutters are mounted on the front face plate and also on the outriggerbucket members. As the head rotates and at the same time advances, thebucket members follow a spiral path along the circumference of the endwall of the tunnel and act to scoop up rock and other debris cut by thecutters from such end wall. The buckets carry the debris to the top ofthe machine. Here the contents of the buckets discharge by gravity ontoan endless conveyor which carries the debris to the rear of the machine.

Each of said cutters has a freely rotating wheel bevelled to form acircumferential cutting edge. The axis of rotation of each wheel of theseveral cutters which are mounted on the face plate, and in somemachines some of the cutters carried by the bucket members, intersectsthe axis of rotation of the head at a point located slightly to thefront of the face plate. These cutters are spaced both radially andcircumferentially with respect to the heads rotary axis and are commonlytermed the forward facing cutters. As the head rotates and the ma chinepushes forward from its shoe mounts to give the rotating head itsprogressive axial motion, the circumferential cutting edge of each ofthese forward facing wheels bears against the end face of the tunnel,and by virtue of the combined forcesthrust and rotationcuts one of aplurality of concentric closely-spaced circular kerfs therein.

While most of the cutters are of said forward facing type, there areother cutters which perform a gauge function and are known by this term.The gauge cutters are carried by the outrigger bucket members to occupyouter positions relative to the rotary head. They have their cuttingedges directed forwardly and outwardly at various angles to shape theside walls of the tunnel by cutting kerfs in the circumferential cornerof the tunnel, namely where the side and end walls of the tunnel meet.The plane in which the cutting edge of the outermost of these gaugecutters lies is placed almost normal to the rotary axis of the head,with only a slight forward cant, so that as the machine advances it cutsa generally helical kerf in the tunnel side wall.

As each cutter deepens its kerf by chipping away relatively small piecesof adjacent rock, the side faces of the bevelled wheel press inwedge-like fashion into the walls of the kerf to fracture the rock alongplanes reaching from each kerf into the rock. Since, as hereinbeforestated, the cutters which form adjacent kerfs are spacedcircumferentially as well as radially with respect to one another, anygiven portion of the rock between such adjacent kerfs is pressed only bya single cutter at any one time so that the fracturing action is passedinto the rock portion first from the kerf on one side thereof and thenfrom the kerf on the other side. This causes pieces of rock to be brokenfree from the end wall of the tunnel, which pieces fall to the floor ofthe tunnel to be scooped up by the buckets and dumped onto the conveyorfor delivery to the rear of the advancing machine.

Not only does the resistance of the rock to cutting abrade or wear awaythe cutter portions which contact the rock, but the cutters are severelystressed by the various thrust loads exerted by the rock surfaces whichdefine the kerf. Thus one of the problems to be solved in devising thecutters and their associated support structure is that of constructingthe same with sufiicient ruggedness and durability to be able to standup under such conditions. Even then, the cutters must have periodicmaintenance, which is accomplished by backing off the machine from thetunnel end wall a distance suificient to permit access by a mechanic tothe front of the machine for replacement of parts that are damaged orunduly worn. However, even with the machine backed off, the proximity ofoutermost gauge cutters to the side wall of the tunnel has madeservicing of these particular cutters relatively difficult.

Follow-up work in a tunnel being bored is considerably less difiicult ifthe cut given to the cylindnically curved side wall of the tunnel iswithin reason-ably close tolerances. Since it is not always possible todetermine beforehand (because of the nature of the rock encountered,

etc.) what the precise location of the cutters should be to form thetunnel side wall within such tolerances, and since it may be necessary,on occasion, to reinforce a section of wall and consequently expand thediameter of the tunnel by an amount sufiicient to accept awall-reinforcing sleeve, the ability to adjust the gauge cutters tomodify the tunnel diameter as the head works any given section of thetunnel is highly desirable.

It is with the foregoing problems in mind that the apparatus of thepresent invention has been devised, the general object of the inventionbeing to provide for a boring machine of the type described a new andimproved mounting for the gauge cutters, and especially one enabling thecutters to be easily backed away from the side wall of the tunnel togive uninhibited access to the cutters when servicing is required, andone which also permits the gauge cutters to be set in selected radiallyadjusted workingposition-s so that a change in the diameter of thetunnel may be readily obtained.

Other more particular objects and advantages of the invention will, withthe foregoing, appear and be understood in the course of the followingdescription and claims, the invention consisting in the novelconstruction and in the adaptation and combination of parts hereinafterdescribed and claimed.

In the accompanying drawings:

FIGURE 1 is a front elevational view illustrating the rotary head of atunnel-boring machine, equipped with gauge cutter mountings constructedto embody preferred teachings of the present invention.

FIG. 2 is a fragmentary longitudinal vertical sectional view on thejogged section line 2-2 of FIG. 1.

FIG. 3 is a fragmentary transverse vertical sectional view drawn to anenlarged scale on line 33 of FIG. 2.

FIG. 4 is a fragmentary longitudinal vertical sectional view drawn to ayet larger scale on jogged line 4-4 of 'FIG. 3; and

FIG. 5 is an enlargedecale fragmentary sectional view on line 5-5 ofFIG. 3 to detail one of two removable pins employed to set the gaugecutters in a selected one of several radially adjusted positions.

Referring to said drawings, the numeral generally designates a headmember which is journaled for rotation on the front end of the mainframe or body 11 of the machine. The bearing therefor provides an innerrace '12 fixed to the head and an outer race '13 fixed to the mainframe. The inner race functions as a bull gear, being formed about itsinner perimeter with internal teeth. Motor-driven pinions (not shown)mesh the bull gear at spaced intervals of the circumference to drive thehead in its rotary motion. Wall-engaging shoes 14 are carried forradial-motion by the main frame, occupying circumferentially spacedpositions immediately to the rear of the rotary head, and operativelyconnected with these shoes for extending and retracting the same to andfrom the normal Working positions in which the same are illustrated inFIG. 2 are hydraulic jacks 15. These shoes slide along the Wall as themachines main frame advances. While unimportant to an understanding ofthe present invention, the exact manner in which the machine is or maybe operated and a structure suitable to perform 'such operation is fullydescribed in the aforesaid copending application for Letters Patentfiled February 18, 1963, Serial Number 259,275.

The head extends forwardly beyond the shoes 14, giving much theappearance of a cylindrical nose with its diameter considerably lessthan the diameter of the tunnel and with the peripheral wall 16concentric to the rotary axis of the head. The face wall 17 of the headis or may be moderately crowned and has a door 18 in its center throughwhich access to the front of the head is provided when servicing of thecutters is required. As hereinbefore pointed out, the cutters providedare of both the forward facing and gauge type, and in each instance arecarried by mounting blocks. The cutters each desirably have a non-rotaryaxle on which the bevelled cut- .ting wheel is journaled for freerotation, and the mounting blocks therefor desirably are of the splittype each providing boltably connected base end cap components clampingthe ends of an axle therebetween. It will be apparent that thisdescribed type of mounting permits wheel-and-axle replacements to beeasily and quickly applied to the head of the machine simply by seatingthe ends of the axle in the saddle notches of a blocks base component,and applying the cap component to clamp the replacement in place.

The mounting blocks 20 for the forward facing cutters are rigidlysecured, preferably by welding, to the rotary head. Some of the gaugecutters have their mounting blocks, as 21, rigidly secured either to therotary head or to outrigger buckets, as 22, which are themselves rigidlysecured to the head. Others of the gauge cutters have their mountingblocks 19 hingedly supported so that the cutters can be swung inwardlyand outwardly into positions radially adjusted relative to the head. Thehinge attachment may be from the base component of the block directlywith the head or with an outrigger bucket which is fixed to the head, anarrangement which was shown and described in our above-identifiedapplication Serial Number 259,275, or from head to an outrigger buckethaving the base component of the block rigidly secured thereto. Themachine is here shown with this latter type of hinge attachment.

The hinged buckets are denoted by 23 and 24, the distinction being thatthe buckets 23 carry the mounting for only a single gauge cutter whilemountings for two gauge cutters are carried by the buckets 24. Thesebuckets are shown as being four in number located at quarter-circleintervals of the circumference, alternating to have a pair ofdiametrically oppositely disposed buckets 23 and a pair of diametricallyoppositely disposed buckets 24. Pockets 25 are provided in the wall 16of the head to receive the buckets, such pockets being open both to theexterior and to the interior of the head.

Each of the buckets 22, 23 and 24 is a fabricated structure having itsparts joined by welding, and has the shape, more or less, of a hollowrectangular prism. An open ing is provided in the leading end wall andin the bottom wall of each bucket. Said term leading, and the termtrailing whichwill also be employed, are referenced to the positionsoccupied when the bucket is turning with the head in the rotary motionof the latter. Openings formed in the wall 16 of the head, mid-way orapproximately midway between the pockets 2'5 and, like said pockets,leading to the interior of the head, each register with the bottomopening of a respective one of the fixed buckets 22'.

Said opening in the leading wall of each bucket produces a mouth throughwhich debris, scooped up from the floor. of the tunnel as the bucketturns with the head, is delivered to the interior of the bucket fordischarge through the opening which is provided'in the bottom wall..This discharge takes place only as the bucket, upon reaching a positionat the top of the head, is brought mto register with a chute 26 carriedby the main frame of the machine as a stationary part thereof. Thedumped debris falls onto the upper run of a power-driven endlessconveyor belt 27. The scoop action is performed by a lip 28 extendingbeyond the plane of the ingress mouth as a forwardly biased'prolongationof the outer portion of the buckets front wall 34i In the instance ofthe hinged buckets 23'and 24, rearwardly extending flanges 30 areproduced by prolonging the two end walls, namely'the leading wall 31 andthe trailing wall 32. (Jo-axial pins 33 hingedly connect the inner endof these flanges to the end walls of a respective pocket 25 for radialswing motion of the concerned bucket about a transverse axis normal to aradial plane bisecting the concerned pocket. The interior profile of thefront wall of the pocket is arcuate, developed about the hinge pins as acenter, and a slot, shown as full-width, is provided in such wall. Thefront wall 34'of the concerned bucket has a moderately close mating fit.A pair of transversely spaced ears 35 extend through said slot from thebucket. A wrist pin 36 occupies the space between the ears, beingconnected for rocker motion thereto, and at its center connects by apivot pin 37 with the forked outer end of a toggle arm 38. The inner endof the toggle arm is attached by a ball-joint connection 40 to a ring41.

It will be understood that a respective toggle arm is provided for eachof the several hinged buckets 23 and 24, and that the ring 41 is commonto all four crank arms. The ring is fitted upon an annular neck 42 ofthe rotary head for reciprocal turning motion relative to said headabout the rotary center of the latter as an axis. A double-actinghydraulic jack 43 connects at one end with the'ring and at the other endwith the head to provide a power medium for turning the ring.

Ends walls 31 and 32 of each hinged bucket are bored on coinciding axesto provide a plurality of holes 43, shown as three in number and spacedat predetermined equidistant intervals along an arc having the hingeaxis as its center. By turning the ring 41 a selective co-axial pair ofthese holes can be brought into register with a co-axial pair of holes44 bored in the end walls of the concerned pocket. T-headed pins 45secured by bolts 46 anchor the hinged buckets in the selected position.

When employing the center hole of the set of three holes 43, the bucketsare so disposed that the gauge cutters cut a tunnel of the precisediameter for which the machine has been designed. Should it be foundnecessary or desirable in the course of boring a tunnel to introduce aliner to a particular section, a procedure most usually resulting fromevidence of wall-slufiing, the operator need only remove the anchorpins, turn the regulating ring 41 to bring the inner pair of holes intoregister with the holes 44, and re-insert the anchor pins, whereupon thegauge cutters are extended radially outwardly in the degree necessary toproduce a tunnel of the greater diameter necessary to accommodate theliner. Such liner is shown in phantom in FIG. 2 and designated by theletter S. By moving the hinged buckets to their inner position, thegauge cutters are backed away from the sur rounding wall of the tunnel.The machine is at such time also backed off from the front wall of thetunnel, allowing an operator to open the door 18 and pass through theopening in order to work from a position at the front of the machine.The gauge cutters, having been retracted, give the operator easy accessso that the bolts holding the caps of the mounting blocks can be quicklyremoved and the cutterswheels and axles-lifted from the base componentsof the blocks either to be bodily replaced or serviced.

It will be noted in FIG. 2 that we have shown the outer wall of thebucket as having an opening through which dirt and rock particles maypass from the underside of the gauge cutter wheel into the hollow centerof the bucket. This is highly advantageous as a means of clearing thecutter. While it would appear from this view that the base of themounting block is a part of the bucket, the two are made integral onlyby reason of a weld connection.

It is thought that the invention will have been clearly understood fromthe foregoing description. No limitations are to be implied therefrom,it being our intention that the language of the hereto annexed claimswill be given the broadest interpretation which the same fairly admits.

What we claim is:

1. In a tunnel-boring machine: a non-rotary frame adapted to be advancedin a direction endwise to the tunnel being bored, a rotary headsupported by the frame at the front end thereof and providing -a frontface, cutter means carried upon the front face of the head which byrotation and advance of the head act to remove ground strata from theend wall of the tunnel by forming concentric spaced kenfs therein andfracturing the ground strata between said kerfs, cutter means forremoving ground strata near the peripheral corner of the tunnel wheresaid end wall meets the side wall, said last-named cutter meanscomprising at least one freely rotating bevelled gauge-cutting wheelproviding a cutting edge which is adapted to be directed outwardlytoward the side wall, a member on which said bevelled wheel is mountedand so hingedly attached to the head that the wheel can be adjustablyswung in a direction which is generally radial to the rotary axis of thehead between retracted and extended positions the latter of which placessaid cutting edge of the wheel in operating relation to said cornerground strata, the swing axis about which the mounting member is hingedbeing located substantially closer to the cut prescribed by the fullyextended wheel than to the rotary axis of the head.

2. A tunnel-boring machine according to claim I having means forreleasably setting the mounting member in at least said extendedposition into which the same may be swung.

3. A tunnel-boring machine according to claim I having power meansoperatively interconnected with the mounting member for moving thebevelled wheel in said adjusting swing motion.

4. A machine according to claim 3 in which the power means is comprisedof a hydraulic jack.

5. A tunnel-boring machine according to claim 1 having means forreleasably setting the mounting member in at least the outer of saidselective positions into which the same may be swung, said setting meanscomprising a pin insertable through holes which are brought intoregistration when the member is placed in said outer position.

6. A tunnel-boring machine according to claim 5 in which the mountingmember has a split block carried thereby comprised of cap and basecomponents, and wherein the cutting wheel is carried for rotation by anaxle which is removably clamped between said cap and base components.

7. A tunnel-boring machine according to claim 1 wherein the mountingmember for the bevelled wheel comprises an outrigger scoop bucket, thescoop bucket having a throat into which debris is scooped as the headrotates and leading to a delivery opening through which the collecteddebris is dumped at a given point in each rotation of the head, directaccess being provided to said throat from the underside of the cuttingwheel.

8. A tunnel-boring machine according to claim 7 in which the head has aplurality of said hinged scoop buckets located on the perimeter atspaced intervals of the circumference.

9. A tunnel-boring machine according to claim 7, the head having aplurality of said scoop buckets located on the perimeter at spacedintervals of the circumference of the head, and power means operativelyinterconnected with the several scoop. buckets for moving the gaugecutters in said swing motion and causing the cutters to move in concert.

10. In a tunnel-boring machine, in combination with a non-rotary frameadapted to be advanced in a direction endwise to the tunnel being bored,and a rotary head supported by the frame at the front end thereof, meansfor removing ground strata near the corner of the tunnel where the sideWall meets the end wall thereof comprising a plurality of mountingmembers hingedly connected to the head along the periphery at spacedintervals of the circumference and each supporting a rotary bevelledgauge-cutting wheel having its cutting edge directed outwardly towardthe side wall, the hinge connections of said several mounting membersadjustably supporting the cutting wheels for swing movement of thecutting edges thereof either outwardly from or inwardly toward therotary axis of the head about a respective axis fixed with respect tothe head and normal to a plane which is generally radial to the head.

11. A tunnel-boring machine according to claim 10 having power means forswinging the cutters in their ad justing movement.

12. A tunnel-b0ring machine according to claim 10 in which each bevelledwheel is carried for (free rotation upon an axle, each scoop bucketwhich carries a bevelled wheel hawng the base component of a splitmounting block rigidly attached thereto, each axle with a cutting wheelthereon being secured in place upon the respective mounting block byclamping the ends of the axle between said base component and a capcomplement therefor.

13. In a tunnel-boring machine, in. combination with a non-rotary frameadapted to be advanced in a direc tion 'endwise to the tunnel beingbored, and a rotary head supported by the frame at the 'front endthereof, means for removing ground strata near the corner of the tunnelwhere the side wall meets the end wall thereof comprising a plurality ofcutters hingedly connected to the head along the periphery at spacedintervals of the circumference and each providing a rotary bevelledcutting Wheel having a cutting edge which is directed'outwardly towardthe side wall, the hinge connections of-said several cutters adjustablysupporting the cutters for swing movement of the cutting edges thereofeither outwardly from or inwardly toward the rotary axis of the headabout a respective axis spaced from the side wall of'the tunnel beingbored at distance which is less than the distance to which such axis isspaced from the rotary axis of the head.

14. In a tunnel-boring machine, in'cornbination with a non-rotary frameadapted to be advanced in a direction endwise to the tunnel being bored,and a rotary head supported by the frame at the front end thereof, meansfor removing ground strata near the corner of the tunnel where the sidewall meets the end wall thereof comprising a plurality of-cuttershingedly connected to the head along the periphery at spaced intervalsof the circumference and each providing a cut-tingedge which is directedoutwardly toward the side wall, the hinge connections of said severalcutters supporting the cutters for swing movement of the cutting edgesthereof either'outwardly from or inwardly toward the rotary axis of thehead, and means operatively interconnected with the several hingedlymounted cutters for swinging the several cuttersi-n concert, said meanscomprising a ring mounted upon the head for turning motion about therotary axis of the head and respective toggle arms connecting said ringwith the several cutters.

15. A tunnel-boring machine according to claim 14 having a double-actinghydraulic jack for turning the ring attached at one end to the headandat the other end to the ring.

References Cited by the Examiner UNITED STATES PATENTS 1,462,997 7/1923Anderson 299-61 X 1,517,802 12/ 1924 Sheen 299-61 2,745,650 5/1956 Smith299 2,750,176 6/1956 Cartlidge 299-80 2,756,036 7/1956 McIntyre 29956 X2,801,094 7/1957 Ball 299-80 2,879,049 3/ 1959 Poundstone 299-802,898,742 8/1959 Robbins 29958 X 2,937,859 5/1960 Jackson 299-802,946,578 7/1960 De Sma'ele -62 2,988,348 6/ 1961 Robbins 299-86 X2,998,964 9/1961 Morlan 29961 X 3,035,822 5/ 1962 Lundguistet al 299-613,139,148 6/1964 Robbins 299-86 X CHARLES "E, OCONNELL, PrimaryExaminer. "BENJAMINHERSH, Examiner,

10. IN A TUNNEL-BORING MACHINE, IN COMBINATION WITH A NON-ROTARY FRAMEADAPTED TO BE ADVANCED IN A DIRECTION ENDWISE TO THE TUNNEL BEING BORED,AND A ROTARY HEAD SUPPORTED BY THE FRAME AT THE FRONT END THEREOF, MEANSFOR REMOVING GROUND STRATA NEAR THE CORNER OF THE TUNNEL WHERE THE SIDEWALL MEETS THE END WALL THEREOF COMPRISING A PLURALITY OF MOUNTINGMEMBERS HINGEDLY CONNECTED TO THE HEAD ALONG THE PERIPHERY AT SPACEDINTERVALS OF THE CIRCUMFERENCE AND EACH SUPPORTING A ROTARY BEVELLEDGUAGE-CUTTING WHEEL HAVING ITS CUTTING EDGE DIRECTED OUT-